1. Field of the Invention
The present invention relates to a structure of foaming die which is so designed that a hollow headrest trim cover assembly of generally inverted-L-shape and headrest stays attached thereto are placed therein for an integral foaming operation which involves injecting a liquid foaming agent into the inside of the trim cover assembly and curing it into a foam padding filled therein, and a resulting headrest can be removed therefrom subsequent to the foaming operation, wherein the generally inverted-L-shaped trim cover assembly or headrest body has a horizontal upper portion and a vertical head support portion extending vertically and downwardly from the horizontal upper portion, with the headrest stay extending donwardly from a bottom side of the horizontal upper portion.
2. Description of Prior Art
There has been known a headrest having generally “inverted L” shape as viewed from the lateral side thereof, which is basically formed by a horizontally extending upper portion and a vertically extending head support portion as stated above. This is for example disclosed from the Japanese Laid-Open Publication No. 11-290154. According thereto, a rigid plate member is bent formed into such horizontal top portion and vertical head support portion, and an upholstery is affixed on the outer side of that plate member, while a pair of stays are firmly connected with the horizontal top portion. Hereinafter, this type of headrest shall be referred to as “inverted-L-shaped headrest”.
Normally, in assembly of such inverted-L-shaped headrest, a foaming process has been employed, which involves subjecting a preformed hollow three-dimensional trim cover assembly of “inverted L” shape into foaming integrally together with a headrest frame including an integral pair of stays, using a foaming die.
In this respect, there has been a problem with the foaming die in terms of placing and removing such particular inverted-L-shaped headrest with stays into and from the die. That is, in the case of the foregoing laid-open publication, the foaming die includes a die element or part disposed between the back side of the vertical head support portion of a resulting headrest and the stays extending along that vertical head support portion, as a result of which, it is rather difficult or troublesome to remove the resulting headrest with the stays from the forming die, because of the die element or part standing in the way of the vertical head support portion.
The Japanese Laid-Open Patent Publication No. 10-329151 discloses a foaming die for forming a headrest, which relates to normal headrest without vertically long head support portion and teaches provision of a separate profile retaining plate which can be set and removed into and from a foaming die, the profile retaining plate being adapted to receive a bottom side of the normal headrest within the foaming die, during foaming process. Hence, in that case, the profile retaining plate is first removed before taking out a whole resulting headrest, and therefore, it is easy to remove the resulting headrest with stays from the die. But, if it is applied to the inverted-L-shaped headrest, even the profile retaining plate can hardly be removed from the reverse side of the horizontal top portion. This is because both vertical head support portion and stays extends long from that horizontal top portion, which prevents smooth removal of the profile retaining plate or other equivalent separate die element.